Sparge temp

[waking11]

Tomorrow is AG brew day. 1st attempt.

I have a few questions regarding mash and sparge temps. I'm confused by the few different calculators I've looked at

I have a batch size at 5 gal. The recipe calls for a total of 8.25 gal of water 4.5 gal strike and a mash in at 155 F for 60 min.
I'm not able to determine what temp to sparge at? I'm assuming I use the remaining 3.75 gal. I've read that you should always sparge at 168? I'm not entirely sure how to properly calculate.

The grain bill is 12lbs Marris Otter.

Thank you!

 

[snowveil]

Just in case there's any confusion with the strike/mash temperature, be sure to have your strike temperature at least about 10 degrees above your mash temperature. For your first all grain, I'd strike with your 4.5 gallons at about 15 degrees above your intended mash temperature. Stir the mash thoroughly, then measure your mash temperature in multiple locations. If you're too hot, add cold water to your mash and stir until you hit your desired mash temperature. It is much easier to be a little high on your mash temp and add cold water than it is to be too low on your mash temp and add hot water.

The sparge temperature is not as critical as the mash temp. Shoot for your 168 (I usually add my sparge water at 175 or so and let it settle in the mash [I batch sparge]), but if you are some degrees off don't worry about it.

The reason 168 is recommended is because at temperatures above 168 enzymes in the mash start to denature. In layman's terms, you "lock in" the fermentability of your wort. Try not to sparge above 180, where you risk tannin extraction from the grain, and I wouldn't worry too much about it. If you're below 168 for your sparge the only things you'll really run into are:
a) a potentially more fermentable wort than you intended
b) a slightly lower efficiency into the boil kettle (sugars from the mash are more easily dissolved in warmer water and will be pulled out of the mash during lauter more effectively.

Both of these previous issues are negligible for your first all grain.

The key thing to focus on tomorrow is...TAKE NOTES! The more information you gather the more consistent your results going forward will be. My note book has space to write down:

-Strike water volume and temperature
-Mash temperature / pH (don't worry about pH yet...also, take the temperature both at the beginning and end of the mash)
-First wort runnings volume and gravity reading
-Sparge water volume and temperature (and what temp it settles at in the mash if you desire)
-Total wort volume collected and gravity reading.

If it's feasible, pick up a few pounds of DME to have on hand. Expect that on an average 1.050 beer, your pre-boil gravity will be around ten points lower than your starting gravity. If you're a few gravity points low, add some DME and compensate. If you're a few points too high, you can water your wort down before the boil. Until you work out your system's efficiency you'll need to play around a bit with the numbers if you want to hit a specific target.

Also, RDWHAHB.

If you haven't already read Palmer's How to Brew, look it up online and read the all grain tutorial/walkthrough. It's a great resource.

 

[waking11]

Awesome. Thank you! I appreciate it.

 

[J187]

I love Snow's answer. It's great and informative. I'll add one point for emphasis.. the temps of the sparge are figured on what you can almost consider the hotter the better in order to achieve maximum extraction from the grains... the limit is put on because as Snow told you, you run into tannin extraction etc. I also really applaud his advice about having the DME on hand. I always do when I mash, the easiest way for me is to simply over buy DME for the starter.

 

[waking11]

In brewing process now. My mash temp ended up being 150F. I went with it this 1st time even though my target was 155F. 60 min mash. I sparged at 168 for 10 mins(batch).

My volumes were right on. It's in the boil now and I started it with my target of 6.5 gallons.

The OG I measured preboil and is reading 1.037. The recipe called for an OG of 1.068.

Am I supposed to measure OG before the boil or after boil prior to pitching yeast?

 

[Wolfbrau]

Take an 8 oz sample as you transfer the wort from the boil kettle to the fermentor. If you already transferred to the fermentor, just use a wine thief or the bucket spigot to get it. Let it cool to room temperature, then take a reading. Know or find out what the room temp is. Then use an online calculator to correct the temperature down to the calibrated value of the hydrometer - it's in tiny text on the scale inside the hydrometer, probably 60F or 68F. Ta da! You have your OG.

 

[fmr_army]

Some sound advice above. One quibble that I have is the frequent mention of tannin extraction as a by-product of overly hot water. I usually (batch) sparge with the hottest water I can get (often boiling) and have never had tannins (touch wood).

My reasoning is that hot water will dissolve more sugars, leading to better efficiency. Batch sparging doesn't disturb the pH levels much, so tannins won't extract. To hedge my bets, I add a little lactic acid to the sparge water when I remember.

 

[sandyeggoxj]

I don't reemeber where I saw it but I read an article that said that sparge temperature didn't correlate with sugar extraction. If you ran out of hot water to sparge with you could just use cold. Most people use hot water past the range of amylase so that it denatures a controls the level of conversion.